1. Field of the Invention
The present invention relates to spoiler sunroofs and, more particularly, to an improved mechanism for a spoiler sunroof.
2. Description of Related Art
A sunroof for a vehicle generally includes a panel that is movable with respect to an opening in the roof of the vehicle. A spoiler type sunroof, such as one disclosed in U.S. Pat. No. 5,464,267 the disclosure of which is hereby incorporated by reference herein, is capable of moving between (1) a closed position wherein the sunroof panel substantially seals the opening in the roof, (2) a vent position wherein the panel is angled relative to the roof such that a rearward end of the panel is disposed above the roof, and (3) an open position wherein the sunroof panel is disposed substantially rearwardly of the opening. Specifically, the typical spoiler sunroof includes a pair of tracks on each of which is mounted a lift arm and lift mechanism. The lift arms are connected to the panel and are operatively connected to the lift mechanism so that the lift arms may be pivoted about a forward pivot point. This design requires that the panel be supported in a somewhat cantilevered manner, since all but a forward portion of the sunroof panel is disposed behind the opening when the panel is in the open position.
As such, designs for spoiler type sunroof mechanisms have tended to be somewhat complicated to be able to effect the desired movement of the panel. Additionally, as the sunroof panels are disposed above the roof in the vent and open positions, there is a relatively large force directed onto the panel when the vehicle is moving due to the wind resistance of the panel. Therefore, the mechanisms to support the panel need to be relatively strong to stably support the panel and resist deflection of the mechanism and possible damage to the mechanism itself and/or the panel. However, in previous designs the lift mechanism supports the lift arm on only one side and exerts lifting and support force on the lift arm via that side of the lift arm. This xe2x80x9csingle shear supportxe2x80x9d of the lift arm may allow the lift arm to flexurally displace when a force is exerted on the panel. The displacement of the lift arm can cause damage to the arm itself, the panel, or the mechanism.
One aspect of the present invention provides a sunroof assembly for a vehicle having a roof and an opening therein. The assembly includes a panel structure of a size to close the opening and a pair of elongate track members extending in a longitudinal direction relative to the vehicle and constructed to be mounted to the roof side edge portions of the opening. The assembly also includes a pair of lift arms coupled to the panel structure proximate respective side edge portions thereof. Each lift arm is coupled to one of the track members so as to be capable of (1) pivotal vertical movement to move the panel structure relative to the track members between (a) a closed position wherein the panel structure closes the opening of the roof and (b) a vent position wherein the panel structure is disposed at an angle relative to the opening to provide a vent space between the panel structure and the opening, and (2) sliding movement relative to the track members between (a) the vent position and (b) an open position wherein the panel structure is moved along the track members to uncover the opening. Each lift arm has a cam structure providing a camming surface on each opposing lateral side thereof. The assembly also includes a pair of lifting cam structures slidably coupled to each track member. The lifting cam structures have supports positioned on each lateral side of its respective lifting arm to resist deflection of the lifting arms. The lifting cam structures have camming surfaces engaged with the camming surfaces of the cam structures on the opposing lateral sides of the lift arms. The lifting cam structures and the camming surfaces of the lift arms are configured such that sliding movement of the lifting cam structures along the track members relative to the lift arms creates a camming action to raise the lift arms from the closed position to the vent position.